diff --git a/cmds/atrace/atrace.cpp b/cmds/atrace/atrace.cpp
index a4b00f8..1429bc8 100644
--- a/cmds/atrace/atrace.cpp
+++ b/cmds/atrace/atrace.cpp
@@ -171,6 +171,7 @@
         { OPT,      "events/clk/clk_disable/enable" },
         { OPT,      "events/clk/clk_enable/enable" },
         { OPT,      "events/power/cpu_frequency_limits/enable" },
+        { OPT,      "events/power/suspend_resume/enable" },
     } },
     { "membus",     "Memory Bus Utilization", 0, {
         { REQ,      "events/memory_bus/enable" },
diff --git a/cmds/atrace/atrace.rc b/cmds/atrace/atrace.rc
index f1426b6..6e460a0 100644
--- a/cmds/atrace/atrace.rc
+++ b/cmds/atrace/atrace.rc
@@ -49,6 +49,8 @@
     chmod 0666 /sys/kernel/tracing/events/power/cpu_frequency_limits/enable
     chmod 0666 /sys/kernel/debug/tracing/events/power/gpu_frequency/enable
     chmod 0666 /sys/kernel/tracing/events/power/gpu_frequency/enable
+    chmod 0666 /sys/kernel/debug/tracing/events/power/suspend_resume/enable
+    chmod 0666 /sys/kernel/tracing/events/power/suspend_resume/enable
     chmod 0666 /sys/kernel/debug/tracing/events/cpufreq_interactive/enable
     chmod 0666 /sys/kernel/tracing/events/cpufreq_interactive/enable
     chmod 0666 /sys/kernel/debug/tracing/events/vmscan/mm_vmscan_direct_reclaim_begin/enable
diff --git a/data/etc/car_core_hardware.xml b/data/etc/car_core_hardware.xml
index ad7791e..50f117d 100644
--- a/data/etc/car_core_hardware.xml
+++ b/data/etc/car_core_hardware.xml
@@ -40,7 +40,6 @@
     <feature name="android.software.voice_recognizers" notLowRam="true" />
     <feature name="android.software.backup" />
     <feature name="android.software.home_screen" />
-    <feature name="android.software.print" />
     <feature name="android.software.companion_device_setup" />
     <feature name="android.software.autofill" />
     <feature name="android.software.cant_save_state" />
diff --git a/libs/dumputils/dump_utils.cpp b/libs/dumputils/dump_utils.cpp
index 8e762f1..250f902 100644
--- a/libs/dumputils/dump_utils.cpp
+++ b/libs/dumputils/dump_utils.cpp
@@ -46,6 +46,7 @@
 static const char* hal_interfaces_to_dump[] {
         "android.hardware.audio@2.0::IDevicesFactory",
         "android.hardware.audio@4.0::IDevicesFactory",
+        "android.hardware.audio@5.0::IDevicesFactory",
         "android.hardware.biometrics.face@1.0::IBiometricsFace",
         "android.hardware.bluetooth@1.0::IBluetoothHci",
         "android.hardware.camera.provider@2.4::ICameraProvider",
diff --git a/services/sensorservice/SensorService.cpp b/services/sensorservice/SensorService.cpp
index c11b88e..14ed73d 100644
--- a/services/sensorservice/SensorService.cpp
+++ b/services/sensorservice/SensorService.cpp
@@ -299,14 +299,10 @@
 }
 
 void SensorService::setSensorAccess(uid_t uid, bool hasAccess) {
-    SortedVector< sp<SensorEventConnection> > activeConnections;
-    populateActiveConnections(&activeConnections);
-    {
-        Mutex::Autolock _l(mLock);
-        for (size_t i = 0 ; i < activeConnections.size(); i++) {
-            if (activeConnections[i] != nullptr && activeConnections[i]->getUid() == uid) {
-                activeConnections[i]->setSensorAccess(hasAccess);
-            }
+    ConnectionSafeAutolock connLock = mConnectionHolder.lock(mLock);
+    for (const sp<SensorEventConnection>& conn : connLock.getActiveConnections()) {
+        if (conn->getUid() == uid) {
+            conn->setSensorAccess(hasAccess);
         }
     }
 }
@@ -360,7 +356,7 @@
         if (args.size() > 2) {
            return INVALID_OPERATION;
         }
-        Mutex::Autolock _l(mLock);
+        ConnectionSafeAutolock connLock = mConnectionHolder.lock(mLock);
         SensorDevice& dev(SensorDevice::getInstance());
         if (args.size() == 2 && args[0] == String16("restrict")) {
             // If already in restricted mode. Ignore.
@@ -374,7 +370,7 @@
 
             mCurrentOperatingMode = RESTRICTED;
             // temporarily stop all sensor direct report and disable sensors
-            disableAllSensorsLocked();
+            disableAllSensorsLocked(&connLock);
             mWhiteListedPackage.setTo(String8(args[1]));
             return status_t(NO_ERROR);
         } else if (args.size() == 1 && args[0] == String16("enable")) {
@@ -382,7 +378,7 @@
             if (mCurrentOperatingMode == RESTRICTED) {
                 mCurrentOperatingMode = NORMAL;
                 // enable sensors and recover all sensor direct report
-                enableAllSensorsLocked();
+                enableAllSensorsLocked(&connLock);
             }
             if (mCurrentOperatingMode == DATA_INJECTION) {
                resetToNormalModeLocked();
@@ -473,22 +469,18 @@
             result.appendFormat("Sensor Privacy: %s\n",
                     mSensorPrivacyPolicy->isSensorPrivacyEnabled() ? "enabled" : "disabled");
 
-            result.appendFormat("%zd active connections\n", mActiveConnections.size());
-            for (size_t i=0 ; i < mActiveConnections.size() ; i++) {
-                sp<SensorEventConnection> connection(mActiveConnections[i].promote());
-                if (connection != nullptr) {
-                    result.appendFormat("Connection Number: %zu \n", i);
-                    connection->dump(result);
-                }
+            const auto& activeConnections = connLock.getActiveConnections();
+            result.appendFormat("%zd active connections\n", activeConnections.size());
+            for (size_t i=0 ; i < activeConnections.size() ; i++) {
+                result.appendFormat("Connection Number: %zu \n", i);
+                activeConnections[i]->dump(result);
             }
 
-            result.appendFormat("%zd direct connections\n", mDirectConnections.size());
-            for (size_t i = 0 ; i < mDirectConnections.size() ; i++) {
-                sp<SensorDirectConnection> connection(mDirectConnections[i].promote());
-                if (connection != nullptr) {
-                    result.appendFormat("Direct connection %zu:\n", i);
-                    connection->dump(result);
-                }
+            const auto& directConnections = connLock.getDirectConnections();
+            result.appendFormat("%zd direct connections\n", directConnections.size());
+            for (size_t i = 0 ; i < directConnections.size() ; i++) {
+                result.appendFormat("Direct connection %zu:\n", i);
+                directConnections[i]->dump(result);
             }
 
             result.appendFormat("Previous Registrations:\n");
@@ -515,17 +507,14 @@
 }
 
 void SensorService::disableAllSensors() {
-    Mutex::Autolock _l(mLock);
-    disableAllSensorsLocked();
+    ConnectionSafeAutolock connLock = mConnectionHolder.lock(mLock);
+    disableAllSensorsLocked(&connLock);
 }
 
-void SensorService::disableAllSensorsLocked() {
+void SensorService::disableAllSensorsLocked(ConnectionSafeAutolock* connLock) {
     SensorDevice& dev(SensorDevice::getInstance());
-    for (auto &i : mDirectConnections) {
-        sp<SensorDirectConnection> connection(i.promote());
-        if (connection != nullptr) {
-            connection->stopAll(true /* backupRecord */);
-        }
+    for (const sp<SensorDirectConnection>& connection : connLock->getDirectConnections()) {
+        connection->stopAll(true /* backupRecord */);
     }
     dev.disableAllSensors();
     // Clear all pending flush connections for all active sensors. If one of the active
@@ -537,11 +526,11 @@
 }
 
 void SensorService::enableAllSensors() {
-    Mutex::Autolock _l(mLock);
-    enableAllSensorsLocked();
+    ConnectionSafeAutolock connLock = mConnectionHolder.lock(mLock);
+    enableAllSensorsLocked(&connLock);
 }
 
-void SensorService::enableAllSensorsLocked() {
+void SensorService::enableAllSensorsLocked(ConnectionSafeAutolock* connLock) {
     // sensors should only be enabled if the operating state is not restricted and sensor
     // privacy is not enabled.
     if (mCurrentOperatingMode == RESTRICTED || mSensorPrivacyPolicy->isSensorPrivacyEnabled()) {
@@ -552,14 +541,12 @@
     }
     SensorDevice& dev(SensorDevice::getInstance());
     dev.enableAllSensors();
-    for (auto &i : mDirectConnections) {
-        sp<SensorDirectConnection> connection(i.promote());
-        if (connection != nullptr) {
-            connection->recoverAll();
-        }
+    for (const sp<SensorDirectConnection>& connection : connLock->getDirectConnections()) {
+        connection->recoverAll();
     }
 }
 
+
 // NOTE: This is a remote API - make sure all args are validated
 status_t SensorService::shellCommand(int in, int out, int err, Vector<String16>& args) {
     if (!checkCallingPermission(sManageSensorsPermission, nullptr, nullptr)) {
@@ -734,17 +721,8 @@
         for (int i = 0; i < count; i++) {
              mSensorEventBuffer[i].flags = 0;
         }
+        ConnectionSafeAutolock connLock = mConnectionHolder.lock(mLock);
 
-        // Make a copy of the connection vector as some connections may be removed during the course
-        // of this loop (especially when one-shot sensor events are present in the sensor_event
-        // buffer). Promote all connections to StrongPointers before the lock is acquired. If the
-        // destructor of the sp gets called when the lock is acquired, it may result in a deadlock
-        // as ~SensorEventConnection() needs to acquire mLock again for cleanup. So copy all the
-        // strongPointers to a vector before the lock is acquired.
-        SortedVector< sp<SensorEventConnection> > activeConnections;
-        populateActiveConnections(&activeConnections);
-
-        Mutex::Autolock _l(mLock);
         // Poll has returned. Hold a wakelock if one of the events is from a wake up sensor. The
         // rest of this loop is under a critical section protected by mLock. Acquiring a wakeLock,
         // sending events to clients (incrementing SensorEventConnection::mWakeLockRefCount) should
@@ -818,6 +796,10 @@
             }
         }
 
+        // Cache the list of active connections, since we use it in multiple places below but won't
+        // modify it here
+        const std::vector<sp<SensorEventConnection>> activeConnections = connLock.getActiveConnections();
+
         for (int i = 0; i < count; ++i) {
             // Map flush_complete_events in the buffer to SensorEventConnections which called flush
             // on the hardware sensor. mapFlushEventsToConnections[i] will be the
@@ -869,11 +851,8 @@
                         ALOGE("Dynamic sensor release error.");
                     }
 
-                    size_t numConnections = activeConnections.size();
-                    for (size_t i=0 ; i < numConnections; ++i) {
-                        if (activeConnections[i] != nullptr) {
-                            activeConnections[i]->removeSensor(handle);
-                        }
+                    for (const sp<SensorEventConnection>& connection : activeConnections) {
+                        connection->removeSensor(handle);
                     }
                 }
             }
@@ -882,18 +861,14 @@
         // Send our events to clients. Check the state of wake lock for each client and release the
         // lock if none of the clients need it.
         bool needsWakeLock = false;
-        size_t numConnections = activeConnections.size();
-        for (size_t i=0 ; i < numConnections; ++i) {
-            if (activeConnections[i] != nullptr) {
-                activeConnections[i]->sendEvents(mSensorEventBuffer, count, mSensorEventScratch,
-                        mMapFlushEventsToConnections);
-                needsWakeLock |= activeConnections[i]->needsWakeLock();
-                // If the connection has one-shot sensors, it may be cleaned up after first trigger.
-                // Early check for one-shot sensors.
-                if (activeConnections[i]->hasOneShotSensors()) {
-                    cleanupAutoDisabledSensorLocked(activeConnections[i], mSensorEventBuffer,
-                            count);
-                }
+        for (const sp<SensorEventConnection>& connection : activeConnections) {
+            connection->sendEvents(mSensorEventBuffer, count, mSensorEventScratch,
+                    mMapFlushEventsToConnections);
+            needsWakeLock |= connection->needsWakeLock();
+            // If the connection has one-shot sensors, it may be cleaned up after first trigger.
+            // Early check for one-shot sensors.
+            if (connection->hasOneShotSensors()) {
+                cleanupAutoDisabledSensorLocked(connection, mSensorEventBuffer, count);
             }
         }
 
@@ -912,17 +887,11 @@
 }
 
 void SensorService::resetAllWakeLockRefCounts() {
-    SortedVector< sp<SensorEventConnection> > activeConnections;
-    populateActiveConnections(&activeConnections);
-    {
-        Mutex::Autolock _l(mLock);
-        for (size_t i=0 ; i < activeConnections.size(); ++i) {
-            if (activeConnections[i] != nullptr) {
-                activeConnections[i]->resetWakeLockRefCount();
-            }
-        }
-        setWakeLockAcquiredLocked(false);
+    ConnectionSafeAutolock connLock = mConnectionHolder.lock(mLock);
+    for (const sp<SensorEventConnection>& connection : connLock.getActiveConnections()) {
+        connection->resetWakeLockRefCount();
     }
+    setWakeLockAcquiredLocked(false);
 }
 
 void SensorService::setWakeLockAcquiredLocked(bool acquire) {
@@ -1144,9 +1113,7 @@
     sp<SensorEventConnection> result(new SensorEventConnection(this, uid, connPackageName,
             requestedMode == DATA_INJECTION, connOpPackageName, hasSensorAccess));
     if (requestedMode == DATA_INJECTION) {
-        if (mActiveConnections.indexOf(result) < 0) {
-            mActiveConnections.add(result);
-        }
+        mConnectionHolder.addEventConnectionIfNotPresent(result);
         // Add the associated file descriptor to the Looper for polling whenever there is data to
         // be injected.
         result->updateLooperRegistration(mLooper);
@@ -1162,7 +1129,7 @@
 sp<ISensorEventConnection> SensorService::createSensorDirectConnection(
         const String16& opPackageName, uint32_t size, int32_t type, int32_t format,
         const native_handle *resource) {
-    Mutex::Autolock _l(mLock);
+    ConnectionSafeAutolock connLock = mConnectionHolder.lock(mLock);
 
     // No new direct connections are allowed when sensor privacy is enabled
     if (mSensorPrivacyPolicy->isSensorPrivacyEnabled()) {
@@ -1190,9 +1157,8 @@
     }
 
     // check for duplication
-    for (auto &i : mDirectConnections) {
-        sp<SensorDirectConnection> connection(i.promote());
-        if (connection != nullptr && connection->isEquivalent(&mem)) {
+    for (const sp<SensorDirectConnection>& connection : connLock.getDirectConnections()) {
+        if (connection->isEquivalent(&mem)) {
             ALOGE("Duplicate create channel request for the same share memory");
             return nullptr;
         }
@@ -1229,7 +1195,7 @@
         return nullptr;
     }
 
-    SensorDirectConnection* conn = nullptr;
+    sp<SensorDirectConnection> conn;
     SensorDevice& dev(SensorDevice::getInstance());
     int channelHandle = dev.registerDirectChannel(&mem);
 
@@ -1246,7 +1212,7 @@
     } else {
         // add to list of direct connections
         // sensor service should never hold pointer or sp of SensorDirectConnection object.
-        mDirectConnections.add(wp<SensorDirectConnection>(conn));
+        mConnectionHolder.addDirectConnection(conn);
     }
     return conn;
 }
@@ -1358,7 +1324,7 @@
 }
 
 void SensorService::cleanupConnection(SensorEventConnection* c) {
-    Mutex::Autolock _l(mLock);
+    ConnectionSafeAutolock connLock = mConnectionHolder.lock(mLock);
     const wp<SensorEventConnection> connection(c);
     size_t size = mActiveSensors.size();
     ALOGD_IF(DEBUG_CONNECTIONS, "%zu active sensors", size);
@@ -1391,10 +1357,10 @@
         }
     }
     c->updateLooperRegistration(mLooper);
-    mActiveConnections.remove(connection);
+    mConnectionHolder.removeEventConnection(connection);
     BatteryService::cleanup(c->getUid());
     if (c->needsWakeLock()) {
-        checkWakeLockStateLocked();
+        checkWakeLockStateLocked(&connLock);
     }
 
     {
@@ -1414,7 +1380,7 @@
 
     SensorDevice& dev(SensorDevice::getInstance());
     dev.unregisterDirectChannel(c->getHalChannelHandle());
-    mDirectConnections.remove(c);
+    mConnectionHolder.removeDirectConnection(c);
 }
 
 sp<SensorInterface> SensorService::getSensorInterfaceFromHandle(int handle) const {
@@ -1433,7 +1399,7 @@
         return BAD_VALUE;
     }
 
-    Mutex::Autolock _l(mLock);
+    ConnectionSafeAutolock connLock = mConnectionHolder.lock(mLock);
     if (mCurrentOperatingMode != NORMAL
            && !isWhiteListedPackage(connection->getPackageName())) {
         return INVALID_OPERATION;
@@ -1484,7 +1450,7 @@
                             }
                             connection->sendEvents(&event, 1, nullptr);
                             if (!connection->needsWakeLock() && mWakeLockAcquired) {
-                                checkWakeLockStateLocked();
+                                checkWakeLockStateLocked(&connLock);
                             }
                         }
                     }
@@ -1497,9 +1463,7 @@
         BatteryService::enableSensor(connection->getUid(), handle);
         // the sensor was added (which means it wasn't already there)
         // so, see if this connection becomes active
-        if (mActiveConnections.indexOf(connection) < 0) {
-            mActiveConnections.add(connection);
-        }
+        mConnectionHolder.addEventConnectionIfNotPresent(connection);
     } else {
         ALOGW("sensor %08x already enabled in connection %p (ignoring)",
             handle, connection.get());
@@ -1603,7 +1567,7 @@
         }
         if (connection->hasAnySensor() == false) {
             connection->updateLooperRegistration(mLooper);
-            mActiveConnections.remove(connection);
+            mConnectionHolder.removeEventConnection(connection);
         }
         // see if this sensor becomes inactive
         if (rec->removeConnection(connection)) {
@@ -1762,22 +1726,19 @@
 }
 
 void SensorService::checkWakeLockState() {
-    Mutex::Autolock _l(mLock);
-    checkWakeLockStateLocked();
+    ConnectionSafeAutolock connLock = mConnectionHolder.lock(mLock);
+    checkWakeLockStateLocked(&connLock);
 }
 
-void SensorService::checkWakeLockStateLocked() {
+void SensorService::checkWakeLockStateLocked(ConnectionSafeAutolock* connLock) {
     if (!mWakeLockAcquired) {
         return;
     }
     bool releaseLock = true;
-    for (size_t i=0 ; i<mActiveConnections.size() ; i++) {
-        sp<SensorEventConnection> connection(mActiveConnections[i].promote());
-        if (connection != nullptr) {
-            if (connection->needsWakeLock()) {
-                releaseLock = false;
-                break;
-            }
+    for (const sp<SensorEventConnection>& connection : connLock->getActiveConnections()) {
+        if (connection->needsWakeLock()) {
+            releaseLock = false;
+            break;
         }
     }
     if (releaseLock) {
@@ -1793,17 +1754,6 @@
     }
 }
 
-void SensorService::populateActiveConnections(
-        SortedVector< sp<SensorEventConnection> >* activeConnections) {
-    Mutex::Autolock _l(mLock);
-    for (size_t i=0 ; i < mActiveConnections.size(); ++i) {
-        sp<SensorEventConnection> connection(mActiveConnections[i].promote());
-        if (connection != nullptr) {
-            activeConnections->add(connection);
-        }
-    }
-}
-
 bool SensorService::isWhiteListedPackage(const String8& packageName) {
     return (packageName.contains(mWhiteListedPackage.string()));
 }
@@ -1938,4 +1888,62 @@
     }
     return binder::Status::ok();
 }
-}; // namespace android
+
+SensorService::ConnectionSafeAutolock::ConnectionSafeAutolock(
+        SensorService::SensorConnectionHolder& holder, Mutex& mutex)
+        : mConnectionHolder(holder), mAutolock(mutex) {}
+
+template<typename ConnectionType>
+const std::vector<sp<ConnectionType>>& SensorService::ConnectionSafeAutolock::getConnectionsHelper(
+        const SortedVector<wp<ConnectionType>>& connectionList,
+        std::vector<std::vector<sp<ConnectionType>>>* referenceHolder) {
+    referenceHolder->emplace_back();
+    std::vector<sp<ConnectionType>>& connections = referenceHolder->back();
+    for (const wp<ConnectionType>& weakConnection : connectionList){
+        sp<ConnectionType> connection = weakConnection.promote();
+        if (connection != nullptr) {
+            connections.push_back(std::move(connection));
+        }
+    }
+    return connections;
+}
+
+const std::vector<sp<SensorService::SensorEventConnection>>&
+        SensorService::ConnectionSafeAutolock::getActiveConnections() {
+    return getConnectionsHelper(mConnectionHolder.mActiveConnections,
+                                &mReferencedActiveConnections);
+}
+
+const std::vector<sp<SensorService::SensorDirectConnection>>&
+        SensorService::ConnectionSafeAutolock::getDirectConnections() {
+    return getConnectionsHelper(mConnectionHolder.mDirectConnections,
+                                &mReferencedDirectConnections);
+}
+
+void SensorService::SensorConnectionHolder::addEventConnectionIfNotPresent(
+        const sp<SensorService::SensorEventConnection>& connection) {
+    if (mActiveConnections.indexOf(connection) < 0) {
+        mActiveConnections.add(connection);
+    }
+}
+
+void SensorService::SensorConnectionHolder::removeEventConnection(
+        const wp<SensorService::SensorEventConnection>& connection) {
+    mActiveConnections.remove(connection);
+}
+
+void SensorService::SensorConnectionHolder::addDirectConnection(
+        const sp<SensorService::SensorDirectConnection>& connection) {
+    mDirectConnections.add(connection);
+}
+
+void SensorService::SensorConnectionHolder::removeDirectConnection(
+        const wp<SensorService::SensorDirectConnection>& connection) {
+    mDirectConnections.remove(connection);
+}
+
+SensorService::ConnectionSafeAutolock SensorService::SensorConnectionHolder::lock(Mutex& mutex) {
+    return ConnectionSafeAutolock(*this, mutex);
+}
+
+} // namespace android
diff --git a/services/sensorservice/SensorService.h b/services/sensorservice/SensorService.h
index e6ec96d..060b5eb 100644
--- a/services/sensorservice/SensorService.h
+++ b/services/sensorservice/SensorService.h
@@ -20,6 +20,7 @@
 #include "SensorList.h"
 #include "RecentEventLogger.h"
 
+#include <android-base/macros.h>
 #include <binder/AppOpsManager.h>
 #include <binder/BinderService.h>
 #include <binder/IUidObserver.h>
@@ -42,6 +43,7 @@
 #include <sys/types.h>
 #include <unordered_map>
 #include <unordered_set>
+#include <vector>
 
 #if __clang__
 // Clang warns about SensorEventConnection::dump hiding BBinder::dump. The cause isn't fixable
@@ -95,10 +97,67 @@
     friend class BinderService<SensorService>;
 
     // nested class/struct for internal use
-    class SensorRecord;
+    class ConnectionSafeAutolock;
+    class SensorConnectionHolder;
     class SensorEventAckReceiver;
+    class SensorRecord;
     class SensorRegistrationInfo;
 
+    // Promoting a SensorEventConnection or SensorDirectConnection from wp to sp must be done with
+    // mLock held, but destroying that sp must be done unlocked to avoid a race condition that
+    // causes a deadlock (remote dies while we hold a local sp, then our decStrong() call invokes
+    // the dtor -> cleanupConnection() tries to re-lock the mutex). This class ensures safe usage
+    // by wrapping a Mutex::Autolock on SensorService's mLock, plus vectors that hold promoted sp<>
+    // references until the lock is released, when they are safely destroyed.
+    // All read accesses to the connection lists in mConnectionHolder must be done via this class.
+    class ConnectionSafeAutolock final {
+    public:
+        // Returns a list of non-null promoted connection references
+        const std::vector<sp<SensorEventConnection>>& getActiveConnections();
+        const std::vector<sp<SensorDirectConnection>>& getDirectConnections();
+
+    private:
+        // Constructed via SensorConnectionHolder::lock()
+        friend class SensorConnectionHolder;
+        explicit ConnectionSafeAutolock(SensorConnectionHolder& holder, Mutex& mutex);
+        DISALLOW_IMPLICIT_CONSTRUCTORS(ConnectionSafeAutolock);
+
+        // NOTE: Order of these members is important, as the destructor for non-static members
+        // get invoked in the reverse order of their declaration. Here we are relying on the
+        // Autolock to be destroyed *before* the vectors, so the sp<> objects are destroyed without
+        // the lock held, which avoids the deadlock.
+        SensorConnectionHolder& mConnectionHolder;
+        std::vector<std::vector<sp<SensorEventConnection>>> mReferencedActiveConnections;
+        std::vector<std::vector<sp<SensorDirectConnection>>> mReferencedDirectConnections;
+        Mutex::Autolock mAutolock;
+
+        template<typename ConnectionType>
+        const std::vector<sp<ConnectionType>>& getConnectionsHelper(
+                const SortedVector<wp<ConnectionType>>& connectionList,
+                std::vector<std::vector<sp<ConnectionType>>>* referenceHolder);
+    };
+
+    // Encapsulates the collection of active SensorEventConection and SensorDirectConnection
+    // references. Write access is done through this class with mLock held, but all read access
+    // must be routed through ConnectionSafeAutolock.
+    class SensorConnectionHolder {
+    public:
+        void addEventConnectionIfNotPresent(const sp<SensorEventConnection>& connection);
+        void removeEventConnection(const wp<SensorEventConnection>& connection);
+
+        void addDirectConnection(const sp<SensorDirectConnection>& connection);
+        void removeDirectConnection(const wp<SensorDirectConnection>& connection);
+
+        // Pass in the mutex that protects this connection holder; acquires the lock and returns an
+        // object that can be used to safely read the lists of connections
+        ConnectionSafeAutolock lock(Mutex& mutex);
+
+    private:
+        friend class ConnectionSafeAutolock;
+        SortedVector< wp<SensorEventConnection> > mActiveConnections;
+        SortedVector< wp<SensorDirectConnection> > mDirectConnections;
+    };
+
     // If accessing a sensor we need to make sure the UID has access to it. If
     // the app UID is idle then it cannot access sensors and gets no trigger
     // events, no on-change events, flush event behavior does not change, and
@@ -250,7 +309,7 @@
     // method checks whether all the events from these wake up sensors have been delivered to the
     // corresponding applications, if yes the wakelock is released.
     void checkWakeLockState();
-    void checkWakeLockStateLocked();
+    void checkWakeLockStateLocked(ConnectionSafeAutolock* connLock);
     bool isWakeLockAcquired();
     bool isWakeUpSensorEvent(const sensors_event_t& event) const;
 
@@ -268,10 +327,6 @@
     // Send events from the event cache for this particular connection.
     void sendEventsFromCache(const sp<SensorEventConnection>& connection);
 
-    // Promote all weak referecences in mActiveConnections vector to strong references and add them
-    // to the output vector.
-    void populateActiveConnections( SortedVector< sp<SensorEventConnection> >* activeConnections);
-
     // If SensorService is operating in RESTRICTED mode, only select whitelisted packages are
     // allowed to register for or call flush on sensors. Typically only cts test packages are
     // allowed.
@@ -306,10 +361,10 @@
 
     // temporarily stops all active direct connections and disables all sensors
     void disableAllSensors();
-    void disableAllSensorsLocked();
+    void disableAllSensorsLocked(ConnectionSafeAutolock* connLock);
     // restarts the previously stopped direct connections and enables all sensors
     void enableAllSensors();
-    void enableAllSensorsLocked();
+    void enableAllSensorsLocked(ConnectionSafeAutolock* connLock);
 
     static uint8_t sHmacGlobalKey[128];
     static bool sHmacGlobalKeyIsValid;
@@ -327,12 +382,13 @@
     mutable Mutex mLock;
     DefaultKeyedVector<int, SensorRecord*> mActiveSensors;
     std::unordered_set<int> mActiveVirtualSensors;
-    SortedVector< wp<SensorEventConnection> > mActiveConnections;
+    SensorConnectionHolder mConnectionHolder;
     bool mWakeLockAcquired;
     sensors_event_t *mSensorEventBuffer, *mSensorEventScratch;
+    // WARNING: these SensorEventConnection instances must not be promoted to sp, except via
+    // modification to add support for them in ConnectionSafeAutolock
     wp<const SensorEventConnection> * mMapFlushEventsToConnections;
     std::unordered_map<int, SensorServiceUtil::RecentEventLogger*> mRecentEvent;
-    SortedVector< wp<SensorDirectConnection> > mDirectConnections;
     Mode mCurrentOperatingMode;
 
     // This packagaName is set when SensorService is in RESTRICTED or DATA_INJECTION mode. Only
diff --git a/services/surfaceflinger/Layer.cpp b/services/surfaceflinger/Layer.cpp
index d6e86eb..fdf9da3 100644
--- a/services/surfaceflinger/Layer.cpp
+++ b/services/surfaceflinger/Layer.cpp
@@ -2048,7 +2048,7 @@
     InputWindowInfo info = mDrawingState.inputInfo;
 
     if (info.displayId == ADISPLAY_ID_NONE) {
-        info.displayId = mDrawingState.layerStack;
+        info.displayId = getLayerStack();
     }
 
     ui::Transform t = getTransform();
diff --git a/services/surfaceflinger/Scheduler/LayerInfo.h b/services/surfaceflinger/Scheduler/LayerInfo.h
index a733781..17afdda 100644
--- a/services/surfaceflinger/Scheduler/LayerInfo.h
+++ b/services/surfaceflinger/Scheduler/LayerInfo.h
@@ -109,7 +109,7 @@
         bool isLowActivityLayer() const {
             // We want to make sure that we received more than two frames from the layer
             // in order to check low activity.
-            if (mElements.size() < 2) {
+            if (mElements.size() < scheduler::LOW_ACTIVITY_BUFFERS + 1) {
                 return false;
             }
 
@@ -118,7 +118,8 @@
             // Check the frame before last to determine whether there is low activity.
             // If that frame is older than LOW_ACTIVITY_EPSILON_NS, the layer is sending
             // infrequent updates.
-            if (mElements.at(mElements.size() - 2) < obsoleteEpsilon) {
+            if (mElements.at(mElements.size() - (scheduler::LOW_ACTIVITY_BUFFERS + 1)) <
+                obsoleteEpsilon) {
                 return true;
             }
 
diff --git a/services/surfaceflinger/Scheduler/Scheduler.cpp b/services/surfaceflinger/Scheduler/Scheduler.cpp
index 5a98232..f8bd958 100644
--- a/services/surfaceflinger/Scheduler/Scheduler.cpp
+++ b/services/surfaceflinger/Scheduler/Scheduler.cpp
@@ -567,9 +567,13 @@
     }
 
     // Content detection is on, find the appropriate refresh rate with minimal error
-    // TODO(b/139751853): Scan allowed refresh rates only (SurfaceFlinger::mAllowedDisplayConfigs)
-    auto iter = min_element(mRefreshRateConfigs.getRefreshRates().cbegin(),
-                            mRefreshRateConfigs.getRefreshRates().cend(),
+    auto begin = mRefreshRateConfigs.getRefreshRates().cbegin();
+
+    // Skip POWER_SAVING config as it is not a real config
+    if (begin->first == RefreshRateType::POWER_SAVING) {
+        ++begin;
+    }
+    auto iter = min_element(begin, mRefreshRateConfigs.getRefreshRates().cend(),
                             [rate = mContentRefreshRate](const auto& l, const auto& r) -> bool {
                                 return std::abs(l.second->fps - static_cast<float>(rate)) <
                                         std::abs(r.second->fps - static_cast<float>(rate));
diff --git a/services/surfaceflinger/Scheduler/SchedulerUtils.h b/services/surfaceflinger/Scheduler/SchedulerUtils.h
index ced1899..ac10f83 100644
--- a/services/surfaceflinger/Scheduler/SchedulerUtils.h
+++ b/services/surfaceflinger/Scheduler/SchedulerUtils.h
@@ -42,9 +42,11 @@
 // or waiting idle in messaging app, when cursor is blinking.
 static constexpr std::chrono::nanoseconds OBSOLETE_TIME_EPSILON_NS = 1200ms;
 
-// Layer is considered low activity if the buffers come more than LOW_ACTIVITY_EPSILON_NS
-// apart. This is helping SF to vote for lower refresh rates when there is not activity
+// Layer is considered low activity if the LOW_ACTIVITY_BUFFERS buffers come more than
+// LOW_ACTIVITY_EPSILON_NS  apart.
+// This is helping SF to vote for lower refresh rates when there is not activity
 // in screen.
+static constexpr int LOW_ACTIVITY_BUFFERS = 2;
 static constexpr std::chrono::nanoseconds LOW_ACTIVITY_EPSILON_NS = 250ms;
 
 // Calculates the statistical mean (average) in the data structure (array, vector). The
diff --git a/services/surfaceflinger/SurfaceFlinger.cpp b/services/surfaceflinger/SurfaceFlinger.cpp
index ffb7012..23b399f 100644
--- a/services/surfaceflinger/SurfaceFlinger.cpp
+++ b/services/surfaceflinger/SurfaceFlinger.cpp
@@ -1681,7 +1681,8 @@
     setTransactionFlags(eDisplayTransactionNeeded);
 }
 
-bool SurfaceFlinger::previousFrameMissed() NO_THREAD_SAFETY_ANALYSIS {
+bool SurfaceFlinger::previousFrameMissed(int graceTimeMs) NO_THREAD_SAFETY_ANALYSIS {
+    ATRACE_CALL();
     // We are storing the last 2 present fences. If sf's phase offset is to be
     // woken up before the actual vsync but targeting the next vsync, we need to check
     // fence N-2
@@ -1690,7 +1691,15 @@
             ? mPreviousPresentFences[0]
             : mPreviousPresentFences[1];
 
-    return fence != Fence::NO_FENCE && (fence->getStatus() == Fence::Status::Unsignaled);
+    if (fence == Fence::NO_FENCE) {
+        return false;
+    }
+
+    if (graceTimeMs > 0 && fence->getStatus() == Fence::Status::Unsignaled) {
+        fence->wait(graceTimeMs);
+    }
+
+    return (fence->getStatus() == Fence::Status::Unsignaled);
 }
 
 void SurfaceFlinger::populateExpectedPresentTime() NO_THREAD_SAFETY_ANALYSIS {
@@ -1713,7 +1722,15 @@
             // seeing this same value.
             populateExpectedPresentTime();
 
-            bool frameMissed = previousFrameMissed();
+            // When Backpressure propagation is enabled we want to give a small grace period
+            // for the present fence to fire instead of just giving up on this frame to handle cases
+            // where present fence is just about to get signaled.
+            const int graceTimeForPresentFenceMs =
+                    (mPropagateBackpressure &&
+                     (mPropagateBackpressureClientComposition || !mHadClientComposition))
+                    ? 1
+                    : 0;
+            bool frameMissed = previousFrameMissed(graceTimeForPresentFenceMs);
             bool hwcFrameMissed = mHadDeviceComposition && frameMissed;
             bool gpuFrameMissed = mHadClientComposition && frameMissed;
             ATRACE_INT("FrameMissed", static_cast<int>(frameMissed));
diff --git a/services/surfaceflinger/SurfaceFlinger.h b/services/surfaceflinger/SurfaceFlinger.h
index a59a1e0..2718e0e 100644
--- a/services/surfaceflinger/SurfaceFlinger.h
+++ b/services/surfaceflinger/SurfaceFlinger.h
@@ -851,7 +851,7 @@
         return hwcDisplayId ? getHwComposer().toPhysicalDisplayId(*hwcDisplayId) : std::nullopt;
     }
 
-    bool previousFrameMissed();
+    bool previousFrameMissed(int graceTimeMs = 0);
     void setVsyncEnabledInHWC(DisplayId displayId, HWC2::Vsync enabled);
 
     /*